1. Field of the Invention
The present invention relates to a lens module, and more particularly to a lens module having improved structure capable of being fixed to a substrate that carries an image detector firmly and rapidly.
2. The Related Art
The so-called UV glue is a kind of adhesive that needs to be irradiated with ultraviolet light to achieve a solidification effect. It has been widely used in electronics and optoelectronics industries for fixing electronic components or lens modules because of its special property of strong adhesion, rapid solidification, small shrinkage and the like.
In general, a conventional lens module 100′ as shown in FIG. 9 includes a lens barrel 21′ and a lens holder 22′ integratedly formed at a bottom of the lens barrel 21′. The lens barrel 21′ has a hollow receiving groove 211′ for receiving an optical lens 23′ therein. The lens holder 22′ defines a containing cavity 221′ communicating with the receiving groove 211′ and penetrating through a bottom thereof. When the conventional lens module 100′ is to be fixed to a substrate 1′ which has an image detector 3′ fixed at a center thereof, UV glues 4′ are distributed around the lens holder 22′, then ultraviolet lights (not shown) are used to irradiate and solidify the UV glues 4′ to make the conventional lens module 100′ fixed to the substrate 1′.
However, the UV glues 4′ will spread to the containing cavity 221′ during distributing the UV glues 4′ to the lens holder 22′, and the ultraviolet lights can not irradiate the UV glues 4′ which spread to the containing cavity 221′. As a result, the UV glues 4′ can not be solidified completely, and consequently, the conventional lens module 100′ is fixed to the substrate 1′ unstably.